Bag



Dec. 23, 1941. A. PoTDEvlN BAG Filed Jan. 12, 1939 INVENTOR ATTORNEYS,

' Patented Dec. 23, 1941 y BAG Adolph Potdevin, Garden City, NQY., assignor to P'otdevin Machine Company,

tix-poration oi NewYork Brooklyn, Y., a

apncauon January 12, i939, serian No. 250,413 s claims. (ci.l 22a- 55) This invention relates to improvements in bags I and to a method of making Ithe same, being particularly directed to bags of the multi-wall type such as employed for cement,

In the manufacture ofv multi-wall bags of the type indicated, it is usual to tube a plurality of superimposed separate webs of bag making material, th'e tube being 'thereafter cut into bag lengths and bottomed in any desired manner.

The present invention has for one of its objects the provision of a method of making multi-wall'bags wherein it is possible to produce a shingled' multi-wall bag without the necessity of employing a plurality of webs of bag making ma.- terial and without the necessity of employing a separate shingling step.

'A further object of the invention is the provision of a multi-wall bag in which the minimum number of seams is necessary, my invention also lending itself to the use of a cover sheet, such as a printed sheet or a sheet of a diierent material from the rest of the nbag,

-which in many cases is very desirable.

in the accompanying drawing:

Fig. 1 is a perspective view of a web of bag material used in the manufacture of the bag of the present invention together with a diagrammatic view of a mandrel on which th'e material is wound in the process of fabricating the bag;

Fig. 2 is a perspective view of the wound material after removal from the mandrel;

Fig. 3 is a, sectional view taken on line 3-3 of Fig. 2

Fig. 4 is a fragment-ary view of the shingled end of the bag;

A Fig. 5 is a perspective view of the completed bag: and

. Fig. 6 is a sectional view on line 6-6 of Fig. 5.

Referring to the drawing in detail: 2 designates a sheet or web of material'from which the` bagis to be made. As will be seen from the drawing, the sides of this sheet diverge from no claims to novelty as to the mandrel construction being made inthis application.

If the strip is led over the top of the mandrel the narrower and leading end of the strip is provided on its upper face with a transverse stripe of adhesive G adjacent its edge whereby f to secure the strip of material to itself on the rstturn made by the mandrel d. Longitudinal stripes oi' adhesive may also be applied to the web of material adjacent the sides of the web as at 8 and l0. A transverse stripe l2 is also applied to the underside of the trailing of the strip, t

It will be understood that the strip 2 is of a length to make one bag, and after it has been -rolled about the mandrel d, as indicated, it will be appreciated that the edge' of the trailing or wide end of the material will be `adhesively secured to the adjacent face of the material by adhesive stripe l2, as seen from Fig. 2, to pro- I vide an outside seam I4. It'will be noted that there are but two seams in the bag walls, i. e., where the leading end of the strip is secured to the adjacent bag wall, as seen at I3, and where the trailing end is secured to the adjacent bag wall, as. shown at It, already referred to. l

When th'e wound material is removed from the mandrel 4 and collapsed, as illustratedy in Figs. 2 and 3, I have a tube, the ends of the walls of which are stepped or shingled with respect -to each other, the shingling extending helically of the bag. For convenience` in attening the tube after ,it is-removed from the mandrel 4,

lth`e latter may be provided with creasers I5, if

desired.. These will crease the material as it is g wound on the mandrel, as will be appreciated.

As will be seen from Figs. 3 and 4, the shingling extends helically of the bag, the end of the innermost wall it extending helically of the bag gradually merging into the wall i8, the latter has been illustrated merely diagrammatically,

and gradually merging into the contiguous wall l1, the end of the latter extending helically and extending helically to merge into the outer wall i9. The end of this wall does not extend helically because this wall. is constituted by the straight-edged part of the bag material, that is, the part extending from 3 to the trailing end of the strip. y l

It will be appreciated that if one end only of the bag is to be shingled, then only one side edge of the bag material will vextend at an angle to the longitudinal axis of bag material.y ,l

Shouldit be desired to have the outer wall or end the bag composed of a different material than the other Walls of the bag, or a printed sheet, for example, a sheet of this material can be attached to the trailing end of the sheet 2; Such a sheet has been shown at 2l in Fig. 1. This additional sheet is long enough to make one full turn about the bag, and preferably will be straight er the bag tube,4 as shown in Fig. 2, has

' eect, the forming of the multi-Wall bag tube land the shingling being obtained in a single operation.

It is to be understood that various changes may be made in the method herein illustrated and described and in the bag structurewithout departing from the spirit and scope of my invention.

Whatl claim is:

Al. The method of making multi-wall bags, which method comprises Winding a tapered sheet of material upon itself to form a multi-wall tube, the ends of which are stepped or shingled, securing the quterend of the strip to the face of the adjacent wall of the tube, slitting the ends of the tube lengthwise of the tube, folding the corners of the tube inwardly along said slits, and finally folding the ends of the tube intermediate the slits .over upon the folded-in tube corners and sealing, to close the tube.

2. A bag having multi-ply walls comprising a single sheet of material having divergent sides throughout part of its length and parallel sides throughout the remainder of its length, the portion of the sheet having divergent sides and the portion of the sheet having parallel sides extending circumferentially of the bag, and each being of a length equal to at least one circumferential wrap, so that the inner plies of Athe bag walls composed of that portion of the sheet having divergent sides are shingled while the outer plies composed of the straight sided portion of the sheet are of equal lengths.

3. A bag having multi-ply Walls shingled at their ends and composed of a single sheet of material having divergent sides throughout part of its length, and parallel sides throughout the remainder of its length, the portion of the sheet having divergent sides and the portion of the sheet having parallel sides extending circumferentially of the bag, and each being of a length equal to at least one circumferential wrap. said sheet being provided at suitable intervals with stripes of adhesive whereby the plies composing the bag wall are secured to each other.

ADoLPH POTDEVIN.- 

